As a method of decomposing and removing a target which is to be a subject of decomposition, for example, a method of decomposing a target by using a discharge plasma under vacuum or an atmosphere is conventional. This is a method in which molecules in the atmosphere are ionized or dissociated by a discharge plasma to thereby generate positive polarity ions, negative polarity ions and electrons, thereby decomposing and removing harmful substances, such as nitrogen oxides (NOx), volatile organic compounds (VOC), viruses and bacteria in the air.
Also, in the publication of JP 9-75670 A, a method of treating organic pollutants is described in which an organic pollutant treating system including a material having at least one of organic pollutant adsorbing ability, organic pollutant decomposability and microwave absorbing ability, or a combination of these materials and provided with these three characteristics, is allowed to occlude organic pollutants existing in the atmosphere by bringing these pollutants into contact with the system at normal temperature and the treating system is then heated by irradiation with microwaves in an air stream.
Also, in the publication of JP 4-152296 A, a method is described in which a photoelectron releasing material prepared by adding a material which has a relatively large work function and releases photoelectron upon irradiation with ultraviolet rays and/or radial rays to a mother material is used to charge microparticles in gas, thereby collecting and removing these microparticles to obtain purified gas.
In the meantime, as a method of decomposing and removing targets, methods removing targets in a structure partitioned by membranes, for example, a method of removing targets in cells, are conventional. In the case of examining, for example, the function of a protein molecule, or DNA or RNA molecule inside cells or solutions, there are cases where the molecule is decomposed and removed to observe whether the function is developed or not. In this case, when removing some targets from a solution in which a mixture including the targets is dispersed, microparticles whose surfaces are so modified as to have affinity to the targets are introduced, and these microparticles are removed from the solution by using a method such as a centrifuging action to thereby remove these targets at the same time.